vmkfstools -d thin

[goppi]

Hi.

Just tried the following:

vmkfstools -i <source> -d thin <dest> with <dest> beeing located on an NFS datastore.

Console output of vmkfstools is "Destination disk format: VMFS thin-provisioned" however destiantion vmdk has full harddisk size.

Is this normal?

When doing the same with "-d 2gbsparse" destination vmdk(s) are pretty small.

Thanks for your help.

Kind regards

goppi.

[AndreTheGiant]

How do you test the vmdk size?

With ls -l or with du -s ?

Andre

[goppi]

Hi Andre.

Simply looked at what the OS told me.

NFS server is running on Win2003 R2 so explorer told me.

What I also noticed is that thin takes the same time as thik for copying the vmdk (about 10 minutes)

With 2gbsparse it only takes a few seconds.

Regards

goppi

[AndreTheGiant]

Have you tried to create thin disk from vSphere Client?

PS: I do not know if thin disk are supported on NFS.

Andre

[goppi]

>PS: I do not know if thin disk are supported on NFS.

But then I would not expect the console ouput from vmkfstools as stated above.

I tried a different thing. I cloned the disk with commandline above but target datastore was a vmfs datastore with same result meaning ls -l shows exact same size for *flat vmdk file.

Is this what I should expect to see?

Maybe I have a wrong understanding of the thin format at all.

Regards,

goppi.

[GarthDK]

I went through this same confusion last week and here's what I found. First "ls -l" shows the full possible file size, no matter how little of the file is used. Don't know why. "ls -s" shows the actual size of the thin file, not the full size of the file as does "ls -l". Try using "ls -ls" and you'll see what I mean. I tested this out on a test ESXi box and convinced myself that Thin Provisioning works as expected and that you can safely overload a partition as long as you keep close watch so it doesn't run out of space. I used both the Converter and vmkfstools to accomplish thin files. Both worked just fine. I did have a case where the vSphere Client was showing a file much larger than specified and it was showing up when I did a "df" so I deattached the file, cloned the VMDK file using vmkfstools -d thin, and reattached it and all looks fine now.

HTH,

Garth

[DSTAVERT]

NFS from VMware's perspective has always supported thin by default even in 3.5. It is totally dependent on whether the NFS service or OS supports thin.

[goppi]

Hi GarthDK.

Thanks for clarification. I verified this again and what you wrote is exactly how it works.

@DSTAVERT:

Then it seems like NFS for Windows does not support this.

Thanks.